WO 03/054771 A1 describes an electric toothbrush consisting of a handpiece and a replaceable attachable brush. The attachable brush contains a memory in which information identifying the attachable brush is stored. The attachable brush also contains a transponder which outputs the information stored in the memory when it receives an inquiry signal from an inquiry station. The handpiece contains a microcontroller which calculates the cumulative use time of the attachable brush identified and can write this information into the memory of the attachable brush. The handpiece is also provided with a display with which the need for replacing an attachable brush can be displayed.
DE 10 2004 062150 describes a replaceable accessory part for an electric toothbrush and a method for determining the use time of the accessory part.
There are already known electric toothbrushes into which may be inserted a toothpaste bag from which toothpaste can be dispensed during operation of the toothbrush. The bag is replaceable, so that when it is empty, it can be replaced by a filled bag. Electric toothbrushes may also be used by multiple users, in which case each user can attach his own brush head onto/into the hand part of the electric toothbrush and/or can insert his own toothpaste bag. It may happen here that the toothpaste bags are replaced before being completely empty and that toothpaste bags that have only been filled partially and have already been used are used.
EP 0930960 B1 describes a device for body care having a cassette which contains an auxiliary liquid. The cassette is provided with a key, which enables a function of the device when the cartridge is linked to the device.